drivers/nfc/st21nfcb/st21nfcb.c

   1 /*
   2  * NCI based Driver for STMicroelectronics NFC Chip
   3  *
   4  * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/nfc.h>
  21 #include <net/nfc/nci.h>
  22 #include <net/nfc/nci_core.h>
  23
  24 #include "st21nfcb.h"
  25 #include "ndlc.h"
  26
  27 #define DRIVER_DESC "NCI NFC driver for ST21NFCB"
  28
  29 static int st21nfcb_nci_open(struct nci_dev *ndev)
  30 {
  31         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  32         int r;
  33
  34         if (test_and_set_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  35                 return 0;
  36
  37         r = ndlc_open(info->ndlc);
  38         if (r)
  39                 clear_bit(ST21NFCB_NCI_RUNNING, &info->flags);
  40
  41         return r;
  42 }
  43
  44 static int st21nfcb_nci_close(struct nci_dev *ndev)
  45 {
  46         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  47
  48         if (!test_and_clear_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  49                 return 0;
  50
  51         ndlc_close(info->ndlc);
  52
  53         return 0;
  54 }
  55
  56 static int st21nfcb_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
  57 {
  58         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  59
  60         skb->dev = (void *)ndev;
  61
  62         if (!test_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  63                 return -EBUSY;
  64
  65         return ndlc_send(info->ndlc, skb);
  66 }
  67
  68 static struct nci_ops st21nfcb_nci_ops = {
  69         .open = st21nfcb_nci_open,
  70         .close = st21nfcb_nci_close,
  71         .send = st21nfcb_nci_send,
  72 };
  73
  74 int st21nfcb_nci_probe(struct llt_ndlc *ndlc, int phy_headroom,
  75                        int phy_tailroom)
  76 {
  77         struct st21nfcb_nci_info *info;
  78         int r;
  79         u32 protocols;
  80
  81         info = devm_kzalloc(ndlc->dev,
  82                         sizeof(struct st21nfcb_nci_info), GFP_KERNEL);
  83         if (!info)
  84                 return -ENOMEM;
  85
  86         protocols = NFC_PROTO_JEWEL_MASK
  87                 | NFC_PROTO_MIFARE_MASK
  88                 | NFC_PROTO_FELICA_MASK
  89                 | NFC_PROTO_ISO14443_MASK
  90                 | NFC_PROTO_ISO14443_B_MASK
  91                 | NFC_PROTO_NFC_DEP_MASK;
  92
  93         ndlc->ndev = nci_allocate_device(&st21nfcb_nci_ops, protocols,
  94                                         phy_headroom, phy_tailroom);
  95         if (!ndlc->ndev) {
  96                 pr_err("Cannot allocate nfc ndev\n");
  97                 r = -ENOMEM;
  98                 goto err_alloc_ndev;
  99         }
 100         info->ndlc = ndlc;
 101
 102         nci_set_drvdata(ndlc->ndev, info);
 103
 104         r = nci_register_device(ndlc->ndev);
 105         if (r)
 106                 goto err_regdev;
 107
 108         return r;
 109 err_regdev:
 110         nci_free_device(ndlc->ndev);
 111
 112 err_alloc_ndev:
 113         kfree(info);
 114         return r;
 115 }
 116 EXPORT_SYMBOL_GPL(st21nfcb_nci_probe);
 117
 118 void st21nfcb_nci_remove(struct nci_dev *ndev)
 119 {
 120         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
 121
 122         nci_unregister_device(ndev);
 123         nci_free_device(ndev);
 124         kfree(info);
 125 }
 126 EXPORT_SYMBOL_GPL(st21nfcb_nci_remove);
 127
 128 MODULE_LICENSE("GPL");
 129 MODULE_DESCRIPTION(DRIVER_DESC);